Making improvements in the graininess of silver halide photographic materials is an important subject in the field of such materials and much information relating thereto has been accumulated.
For instance, Japanese Patent Application (OPI) No. 62454/80 (corresponding to U.S. Pat. No. 4,264,723) (the term "OPI" as used herein refers to a "published unexamined Japanese patent application") discloses the use of a high speed reactive coupler. Therein, graininess in high density image areas is markedly improved. This is because such a coupler reacts rapidly with oxidation products of color developing agents and, consequently, a development restraining effect caused by oxidation products of color developing agents is diminished and, at the same time, the amount of developed silver in high exposure areas is increased. Under these conditions, all of the coupler molecules coated undergo the reaction and thereby any granular condition becomes inconspicuous, that is to say, disappearance of the granular structure occurs quickly. However, high speed reactive couplers have a serious defect that they form dye clouds of high densities due to the rapid reaction with oxidation products of color developing agents and thereby graininess in low density image areas is extremely deteriorated.
With the intention of obviating such a defect, methods of using high speed reactive couplers in combination with so-called DIR couplers or DIR compounds, which tend to break up dye clouds into fine pieces improving graininess are disclosed in U.S. Pat. Nos. 3,227,554 and 3,632,435, respectively. However, such methods are not desirable because restrainers released upon development counteract the effect of the high speed reactive couplers, that is, the effect of improving the graininess in high density image areas is suffered.